Fluorescent dyes are widely used in biological research and medical diagnostics. Fluorescent dyes are superior to conventional radioactive materials because fluorescent dyes are less expensive and less toxic, and can typically be detected with sufficient sensitivity. In particular, a diversity of fluorophores with a distinguishable color range has made it more practical to perform multiplexed assays capable of detecting multiple biological targets at the same time. The ability to visualize multiple targets in parallel is often required for delineating the spatial and temporal relationships amongst different biological targets in vitro and in vivo. In addition, the generation of a wide range of fluorescent dyes has opened a new avenue for conducting high-throughput and automated assays, thus dramatically reducing the unit cost per assay. Moreover, the low toxicity of fluorescent dyes provides ease of handling in vitro, and also renders it safer for imaging biological activities in vivo.
Fluorescent dyes for applications as described above generally derive from joining a dye and an agent that is capable of binding to a given target or binding partner. Current processes for joining dyes to such binding agents, antibodies being one example, typically require purification of the antibody away from standard buffer components, long reaction times, and purification of the labeled antibody once the reaction is complete. Thus, current processes consume valuable time and resources, and there is a need for improvements in the labeling of binding agents.